Fair Value Measurement (Summary of Change in Fair Value Carrying Amount of Residential Mortgages ) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014		Sep. 30, 2014
Fair Value of Assets Loans Receivable Aggregate Unpaid Principal [Line Items]
Loans Held-for-sale, Fair Value Disclosure	$ 7,781	$ 14,389		$ 19,512
Aggregate Fair Value
Fair Value of Assets Loans Receivable Aggregate Unpaid Principal [Line Items]
Loans Held-for-sale, Fair Value Disclosure		14,389		19,512
Contractual Balance
Fair Value of Assets Loans Receivable Aggregate Unpaid Principal [Line Items]
Loans Held-for-sale, Fair Value Disclosure	7,543	13,873		18,937
Fair Value, Option, Loans Held as Assets, Aggregate Difference	$ 238	$ 516	[1]	$ 575

[1] These changes are included in "Loan sales and servicing income" in the Consolidated Statements of Income.